As I get older, I enjoy listening to the Allman Brothers. Their song, Trouble No More, seems especially appropriate for a recent job that the Kid and I were tag teaming. You know that kind of job that eats up your time, frustrates your efforts, and makes you sing the blues. Someday baby, you ain’t gonna trouble, poor me, anymore.
It Really Wasn't a Difficult Job
That’s how we were feeling after about two weeks. It really wasn’t a difficult job. In fact, just a basic one pump/two baseboard loops residential hot water replacement. Most contractors around here would be in and out in two or three days. You East Coast guys might have it done by noon on the first day. But in the Midwest/Mideast, there isn’t enough demand for boilers for most contractors to have dedicated boiler install crew, so we work with a variety of skill levels.
This contractor definitely didn’t have the resources on this job. The owner is a hard-working guy that has built up quite a nice company over the last 15 years or so, but doing the air side because that’s most of the work around here. When he gets a hydronics job, we now insist that the Kid or I visit the job site before anything gets ordered or any work gets done.
We weren’t quite to that point when this job started. Since the job was over a hundred miles away, the quote came from a series of texted photos of the boiler to be replaced. It was quoted as a top-of-the-line high efficiency model. Once they got the sale, the Kid sketched out the piping. Trouble not yet.
Air in the System?
We delivered the boiler to the contractor and they scheduled the install. The Kid made arrangements to travel to the job site to meet the install crew to go over what needs to be done, like what pipe needs to be cut where, what stays, what goes, etc. The Kid leaves and the crew gets to work—or so it seems.
About a week later, the next contact is from one of their techs that was not on the install crew, but is now there to start up the system. He’s reporting to the Kid that the boiler keeps going off on high limit and that the radiation is not getting warm. Now that is a pretty familiar observation on hot water boilers at their initial start-up and it usually has something to do with air in the system keeping the water from circulating.
The Kid starts asking questions, like, “did you bleed the air out of the radiation”. The tech wasn’t sure because when he got there the install crew was gone to another job, probably a furnace. He did some searching for air vents/bleeders but couldn’t get the boiler to stay on. It was still early fall and warm enough to not need heat yet, so the tech signs off to go to another job (maybe a no cooling call).
We Can't Make This Up
The next tech on the job—again without much hydronics experience—calls to report that he found some air bleeders in the attic, but again no circulation so the boiler keeps locking out on high temperature. At that point the Kid asked for some texted photos of the actual installation. He noticed that the pump was installed in the fill line after the pressure reducing valve and before the fill line connected to the system. Trouble maybe?
Obviously, the pump can’t circulate the water through the boiler and radiation if it is not installed in the boiler piping. Yep, we can’t make this up. The Kid told them to relocate the pump to the supply side as shown on his sketch. Well, the tech can’t do that kind of work, so we wait on the install crew to get off a heat pump job. This job is eating up lots of time at the busy time of year.
Dumb and Dumber
Eventually the pump gets changed, but we still have no circulation. At that point, I look at the photos of how it was installed and spit-up my morning cup of tea. I’m a “flush and plumb” kind of guy and this was “dumb and dumber.” I mean it looked horrible with pipes running at weird angles and directions. I then called the territory manager that handles that account to explain that the job would have to be re-piped and could he talk to the owner.
It was agreed that the Kid would make another trip to go over the piping changes and watch/help them get it right. That meeting didn’t go exactly as planned, since the crew he met didn’t have the time to stay and get the work done that day. Our frustration level is growing.
The weather is changing by now and the homeowner needs heat. The re- piping supposedly gets done and the tech that day gives me a call. I ask him to purge the air out of each baseboard loop with the purge valves that are shown on the sketch. He says that they weren’t installed, but that he can do that right away and call me back. Now I’m feeling the blues.
Light Bulb Moment
When he calls back, he says that nothing is coming out of the open purge valves. No air and no water, which doesn’t make any sense, but nothing has made much sense so far on this job. Since it is two baseboard loops, I went outside the box to ask if they could have hooked the pipes up so that the two supplies were tied together on the supply while the two returns were tied together on the return.
It actually would explain what was going on, but of course the tech that day traced the piping out and assured me it was right. He said it seemed like there was a check valve blocking the flow. That’s when the light bulb went off in my head. I flashed back to a job about five years ago that fit the symptoms.
One of our other contractors without an experienced crew was having the same no circulation issues until I found that they had installed the check valve on a pump backwards. I asked the tech that day to remove the pump to see if there was a check valve installed.
I got the texted photo about ten minutes later. Sure enough, although the piping sketches didn’t indicate a check valve, there it was on the discharge side of the pump, installed backwards, blocking any flow of hot water out of the boiler and any fresh water flow to purge air out of the baseboard loops. He removed the check, re-installed the pump, and purged the two loops. Trouble no more!
Patrick Linhardt is a thirty-nine-year veteran of the wholesale side of the hydronic industry who has been designing and troubleshooting steam and hot water heating systems, pumps and controls on an almost daily basis. An educator and author, he is currently Hydronic Manager at the Corken Steel Products Co.